Island Park, Idaho · field elev 6,596 ft
Density Altitude at Henrys Lake (U53)
Henrys Lake is a genuine high-and-hot field: from 6,596 ft of elevation, a typical July afternoon (80 °F) pushes density altitude to about 9,377 ft — the airplane performs like it is 2,781 ft above the field before the wheels roll.
Typical density altitude by month
| Month | Avg temp °F | DA at avg temp | Afternoon high °F | DA on a typical afternoon |
|---|---|---|---|---|
| January | 13.5 | 5,127 ft | 26.8 | 6,038 ft ▲ |
| February | 16.4 | 5,328 ft | 31.2 | 6,332 ft ▲ |
| March | 24.4 | 5,876 ft | 39.7 | 6,892 ft ▲ |
| April | 34.2 | 6,531 ft | 47.7 | 7,408 ft ▲ |
| May | 43.9 | 7,164 ft | 59.2 | 8,133 ft ⚠ |
| June | 51.2 | 7,631 ft | 68.4 | 8,699 ft ⚠ |
| July | 59.4 | 8,145 ft | 79.7 | 9,377 ft ⚠ |
| August | 57.0 | 7,996 ft | 77.9 | 9,270 ft ⚠ |
| September | 48.6 | 7,466 ft | 67.6 | 8,650 ft ⚠ |
| October | 36.1 | 6,656 ft | 50.8 | 7,605 ft ▲ |
| November | 23.6 | 5,821 ft | 35.9 | 6,643 ft ▲ |
| December | 14.2 | 5,176 ft | 25.8 | 5,970 ft ▲ |
▲ above 5,000 ft · ⚠ above 8,000 ft. These are planning references at standard pressure and dry air — afternoon humidity and low pressure both push the real number higher. Run today's values below.
Run today’s numbers for U53
DENSITY ALTITUDE high DA
Field elevation 6,596 ft — the air behaves like 9,395 ft.
- PRESSURE ALT
- 6,598 ft
- ISA DEVIATION
- —
- RULE-OF-THUMB DA
- —
- AIR DENSITY INDEX
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- AIR DENSITY
- —
- WATER · GRAINS/LB
- —
For training and reference · verify with official sources and your POH before flight · no tool on this site renders a go / no-go judgment
Nearby Idaho fields
- U12 — Stanford Field
St Anthony · elev 4,966 ft
- U41 — Dubois Municipal
Dubois · elev 5,123 ft
- KRXE — Rexburg-Madison County
Rexburg · elev 4,862 ft
- KDIJ — Driggs/Reed Meml
Driggs · elev 6,257 ft
- U56 — Rigby
Rigby · elev 4,845 ft
- 1U2 — Mud Lake/West Jefferson County
Mud Lake · elev 4,795 ft
- KIDA — Idaho Falls Regional
Idaho Falls · elev 4,744 ft
- U00 — Leadore
Leadore · elev 6,029 ft
Frequently asked questions
How high does density altitude get at U53 in summer?
On a typical July afternoon — around 80 °F at the nearest NOAA normals station — density altitude at Henrys Lake reaches roughly 9,377 ft at standard pressure. Hotter-than-normal days, low pressure, and humidity all push it higher, so run the day's actual numbers before flying.
What is the density altitude at U53 on an average day?
It swings with the seasons: from roughly 5,127 ft at the coldest month's average temperature to about 8,145 ft at the warmest month's — all from a constant field elevation of 6,596 ft. The month-by-month table above carries the full year.
What is the field elevation of Henrys Lake?
6,596 ft MSL, from the FAA NASR airport record (28-day cycle effective 2026-08-06). The identifier is U53 (FAA), in Island Park, Idaho.